Flue shield

ABSTRACT

A flue shield comprising a cylindrical body, a first portion and second portion connected at each end of the cylindrical body, each first portion and second portion comprising projections extending radially inward of the cylindrical body, the projections for each of the first portion and second portion being biased in a predetermined axial direction with respect to the cylindrical body, the projections pressingly engagable and slidingly engagable with a pipe, and the first portion and second portion each describing a bore having an inside diameter less than a cylindrical body diameter whereby a space is created between the pipe and the cylindrical body.

FIELD OF THE INVENTION

The invention relates to a flue shield comprising a lanced supportcollar for sliding engagement with a flue pipe.

BACKGROUND OF THE INVENTION

In the art a vent or flue pipe is assembled up through roof trussesbefore the roof deck is installed. Although there may be adequate spacebetween undecked trusses when the vent or flue is initially installed,it is not unusual for the decking to be later installed tightly aroundthe vent or flue pipe without a minimum clear air space as required forfire safety. Correcting this situation requires a contractor to returnto the job to cut a clearance hole in the roof decking around the ventor flue at significant additional expense.

Representative of the art is U.S. Pat. No. 6,997,801 to Green disclosesa roofing vent that includes a base a duct extending from the base. Theduct includes a first end attached to the base and a second end having ahood or cover over the second end. A collar having an aperturetherethrough is mounted from the duct such that the duct extends throughthe aperture, with the collar is slideably supported along the duct andcaptured between the base and the hood or cover.

What is needed is a flue shield comprising a lanced support collar forsliding engagement with a flue pipe. The present invention meets thisneed.

SUMMARY OF THE INVENTION

The primary aspect of the invention is to provide a flue shieldcomprising a lanced support collar for sliding engagement with a fluepipe.

Other aspects of the invention will be pointed out or made obvious bythe following description of the invention and the accompanyingdrawings.

The invention comprises a flue shield comprising a cylindrical body, afirst portion and second portion connected at each end of thecylindrical body, each first portion and second portion comprisingprojections extending radially inward of the cylindrical body, theprojections for each of the first portion and second portion beingbiased in a predetermined axial direction with respect to thecylindrical body, the projections pressingly engagable and slidinglyengagable with a pipe, and the first portion and second portion eachdescribing a bore having an inside diameter less than a cylindrical bodydiameter whereby a space is created between the pipe and the cylindricalbody.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part ofthe specification, illustrate preferred embodiments of the presentinvention, and together with a description, serve to explain theprinciples of the invention.

FIG. 1 is a side view of the flue shield.

FIG. 2 is a detail of a collar.

FIG. 3 is a detail of a collar.

FIG. 4 is an end view of the flue shield at 4-4 on FIG. 1.

FIG. 5 is a side view of the shield installed in a roof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 is a side view of the flue shield. Flue shield 10 comprises acylindrical body 11. Cylindrical body 11 comprises metal or galvanizedmetal suitable for high temperature service.

Engaged with each end of body 11 are collars 12, 13. Each collar 12, 13comprises a bore 30 into which a flue is inserted. Crimps, peens, tackwelds or other suitable adhesive 122, 132 are applied to secure eachcollar 21, 13 to body 11.

Each collar 12, 13 further comprises a lanced portion 121, 131,respectively. Lanced portion 121, 131 comprises an annulus that projectsinward of body 11 in a radial direction. A plurality of radiallyoriented, partial cuts 123, 133 are present in each portion 121, 131,see FIGS. 2, 3. The cuts create a plurality of adjacent projections ortabs 125, 135 that project radially inward of body 11.

Each portion 121, 131 is slightly bent so as to cause each to be flaredor biased in a predetermined axial direction in body 11.

The inside diameter “ID” of each collar 12, 13 is slightly less than anoutside diameter “OD” of a vent or flue pipe 400, see FIGS. 1 and 4.This dimensional feature, along with the tab bias, causes each collar togrip the flue or vent pipe. As the collar grips the flue or vent pipeeach tab 125, 135 is flexed slightly to assure a good grip to preventinadvertent movement of the shield during other construction activitiesthat will occur near the flue or vent pipe. Namely, the projections arepressingly engagable and slidingly engagable with a vent pipe.

The flue shield creates and a gap or air space 200 between the body 11and flue or vent pipe 400. Space 200 prevents contact of the hot fluepipe with roofing materials.

FIG. 2 is a detail of a collar. Radial cuts 123 are disposed on asubstantially equal spacing about portion 121. Tabs 125 are flexible toaccommodate engagement with a vent or flue pipe.

FIG. 3 is a detail of a collar. Radial cuts 133 are disposed on asubstantially equal spacing about portion 131. Tabs 135 are flexible toaccommodate engagement with a vent or flue pipe.

FIG. 4 is an end view of the flue shield at 4-4 on FIG. 1. Shield 10 isinstalled by sliding it down over a flue 400. Flue 400 will usuallyextend through roof trusses to a location coplanar with the roofdecking. Collars 12, 13 center the shield and allow it to be pushed downthe installed flue or pipe 400. The shield keeps the roof decking aminimum distance away from the vent or flue, thereby creating a cool airspace 200 between the vent or flue pipe and the body 11, see FIG. 1. Theshield does not interfere with other vent of flue parts that mayeventually be installed and can be pushed farther down the flue or ventout of the way if necessary after the roof decking has been installed.The shield will stay in position on the flue or vent pipe due to theaction of the flexed tabs 125, 135. Due to the predetermined orientationof tabs, 125, 135, the shield must be installed in a certain direction“D”. The shield will slide over the vent or flue pipe in direction “D”,but cannot be pulled back in the opposite direction. Direction “D” isopposite the direction of the bias of tabs 125, 135.

FIG. 5 is a side view of the shield installed in a roof. Shield 10 isshown in a coplanar position with respect to roof decking “R”. Shield 10is slidingly installed by being pushed in direction “A” down pipe 400.Shield 10 may remain in place through construction completion or may bepushed below the roof line as needed.

Although forms of the invention have been described herein, it will beobvious to those skilled in the art that variations may be made in theconstruction and relation of parts without departing from the spirit andscope of the invention described herein.

1. A flue shield comprising: a cylindrical body; a first portion andsecond portion connected at each end of the cylindrical body; each firstportion and second portion comprising projections extending radiallyinward of the cylindrical body, the projections for each of the firstportion and second portion being biased in a predetermined axialdirection with respect to the cylindrical body, the projectionspressingly engagable and slidingly engagable with a pipe; and the firstportion and second portion each describing a bore having an insidediameter less than a cylindrical body diameter whereby a space iscreated between the pipe and the cylindrical body.